Introduction to Plant Tissue Culture

• Main Author: Razdan, M. K. (Author)
• Format: Book
• Language: English
• Published: Enfield, NH Science Publishers 2003; ©2003
• Edition: Second Edition
• Subjects: Plant tissue culture
• Online Access: Click Here to View Status and Holdings.

 Development of the science of tissue culture is historically linked to the discovery of the cell and subsequent propounding of the cell theory. More than 234 years ago, Henri-Louis Duhamel du Monceau's (1756) pioneering experiments on wound healing in plants demonstrated spon- taneous callus formation on the decorticated region of elm plants. His studies, according noted biologist Gautheret (1985), could be considered a foreword' for the discovery of plant tissue culture. Further contributions to plant tissue culture could be attributed to the cell capable of autonomy en demonsent of the doctrine, which implicitly admitted that a cell is and even potential for totipotency. The body of a higher multicellular multi multiorganed organism from a single-celled zygote supports the totipotent behaviour of a cell. 1. Germination of spores into complete individuals is an obvious sin haplobiontic feature of cells in plants; simila epidermal cells of Begonia are transformed into new begonia plants. In the animal kingdom, a cell from art of a Hydra may give rise to a new any part of a individual. Although these aspects of cellular behaviour point to the totipotent nature of some plant or animal cells, many somatic cells do not produce complete organisms since they form multicellular tissues or organs and are highly differentiated. They are mostly irreversible and lose the meristematic activity. One needs, there- fore, to understand more about the interrelation- ships between the various cells of a tissue and the various organs of an organism. There must be some factor(s) superimposed on theoretically genetically identical cells which brings about certain cellular or subcellular changes leading to morphological differentiat ion. Trécul (1853) observed callus formation in a number of decorticated trees. He published excellent pictures of callus sections and esta blished that apart from the cambium, the medullary rays, phloem, and youngest xylem also contribute as raw materials in the development of tissue culture. An interesting observation made by Vöchting (1878) suggested Observ 'polarity' as a characteristic feature guiding the the development of plant fragments. In his classical of the experiments on stem cuttings, Vöchting observed that the upper portion of a piece of s produced buds and the basal oserved e of stem always region callus or roots. Further, the grafting experiments which he roots undertook among species of Opuntia, Salix, Beta and other trees, demonstrated that behaviour of a is tissue is not altered by contact with other tissue because the dependence of morphogenetic capacity on hereditary internal factors is very strict. Wiesner (1884) proposed a general theory that suggested the existence of organ-forming substances distributed in a polar fashion. Minimal size of explants could be another factor that determined the potential for differentiation.